Improve error log for failed open-debugger fetch (#49295)

Summary:
Pull Request resolved: #49295

Motivated by #49287.

This improves on the less useful output of "fetch failed" currently. We expect failing to make a request to the dev server (made from the dev server!) to be a rare edge case, in which case we want to log as much info as possible.

Changelog: [Internal]

Reviewed By: cipolleschi

Differential Revision: D69395983

fbshipit-source-id: ee96d72ade5a887d190397c3b798a5b545152587

packages/community-cli-plugin/src/commands/start/OpenDebuggerKeyboardHandler.js

@@ -54,8 +54,11 @@ export default class OpenDebuggerKeyboardHandler {
         'Failed to open debugger for %s (%s): %s',
         target.title,
         target.description,
-        e.message,
+        'Network error',
       );
+      if (e.cause != null) {
+        this.#log('error', 'Cause: %s', e.cause);
+      }
       this.#clearTerminalMenu();
     }
   }